Semiconductor device

ABSTRACT

An object of the present invention is to improve the degree of freedom in the wiring design of a wiring substrate configuring a semiconductor device. Lands having an NSMD structure and a land-on-through-hole structure are arranged at positions not overlapping with a plurality of leads arranged on a chip loading surface of a wiring substrate in transparent plan view on the outer peripheral side of a mounting surface of the wiring substrate configuring a semiconductor device having a BGA package structure. On the other hand, land parts having the NSMD structure and to which lead-out wiring parts are connected are arranged at positions overlapping with the leads arranged on the chip loading surface of the wiring substrate in transparent plan view on the inner side than the group of lands in the mounting surface of the wiring substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

The disclosure of Japanese Patent Application No. 2017-087300 filed onApr. 26, 2017 including the specification, drawings and abstract isincorporated herein by reference in its entirety.

BACKGROUND

The present invention relates to a semiconductor device technique, andrelates to a technique effective for applying, for example, asemiconductor device technique including a bump electrode.

For example, Japanese Unexamined Patent Application Publication No.2009-302227 and Japanese Unexamined Patent Application Publication No.2010-93109 describe a structure in which an electrode of a semiconductorchip mounted on a wiring substrate is extracted to the outside through abump electrode arranged on a mounting surface of the wiring substrate.

Japanese Unexamined Patent Application Publication No. 2009-302227discloses a land-on-via structure in which a via penetrating a wiringsubstrate is directly connected with a land where a bump electrode isformed, an NSMD (Non Solder Mask Defined) structure in which the land isincluded in an opening portion of a solder resist formed on a mountingsurface of the wiring substrate, and an SMD (Solder Mask Defined)structure whose peripheral part is covered with the solder resist formedon the mounting surface of the wiring substrate.

Further, Japanese Unexamined Patent Application Publication No.2010-93109 discloses a structure in which a group of solder ballsarranged on the outer peripheral side of a mounting surface of a wiringsubstrate while being circulated in a plurality of rows and a group ofsolder balls arranged on the central side of the mounting surface of thewiring substrate while being circulated in a plurality of rows areprovided on the mounting surface of the wiring substrate.

SUMMARY

By the way, there are many structures of lands (portions to which soldermaterials serving as external terminals are joined) of a wiringsubstrate used for a semiconductor device such as a BGA (Ball GridArray) type or an LGA (Land Grid Array) type.

For example, in the NSMD structure (see FIGS. 10 and 11 of JapaneseUnexamined Patent Application Publication No. 2009-302227), theperipheral part of the land is not covered with an insulating film(solder resist film) , and the land and a part of a wiring (lead-outwiring) connected to the land are exposed from an opening portion formedin the insulating film. Further, for example, in the SMD structure (seeFIGS. 12 and 13 of Japanese Unexamined Patent Application PublicationNo. 2009-302227), the peripheral part of the land and the wiringconnected to the land are covered with the insulating film (solderresist film). In the NSMD structure and the SMD structure, athrough-hole of the wiring substrate is formed at a position notoverlapping with the land. Further, for example, as shown in FIGS. 18and 19 of Japanese Unexamined Patent Application Publication No.2009-302227, there is a land having the NSMD structure in which theperipheral part of the land is not covered with the insulating film anda so-called land-on-through-hole structure (land-on-via structure) inwhich the through-hole (via) of the wiring substrate is formed at aposition overlapping with the land, or a land having the SMD structurein which the peripheral part of the land is covered with the insulatingfilm and the so-called land-on-through-hole structure in which thethrough-hole of the wiring substrate is formed at a position overlappingwith the land.

Here, in the case of the land-on-via structure, since there is no wiringconnected to the land in the same layer as the land, the solder materialbonded to the land can be brought into contact with not only the uppersurface of the land but also the side surface of the land intersectingwith the upper surface. Thus, the land-on-via structure is the mostexcellent in thermal stress resistance among the above-describedstructure proposals. However, according to the study by the inventors,the inventors found that if the land-on-via structure was adopted forall the lands, it was difficult to route a plurality of wiringsconnecting a plurality of leads (bonding leads or bonding fingers)arranged on the upper surface (loading surface of a semiconductor chip)of the wiring substrate to a plurality of lands arranged on the lowersurface (mounting surface) of the wiring substrate.

The other problems and novel features will become apparent from thedescription of the specification and the accompanying drawings.

In a semiconductor device according one embodiment, lands having an NSMDstructure and a land-on-through-hole structure are arranged at positionsnot overlapping with a plurality of leads arranged on a chip loadingsurface of a wiring substrate in transparent plan view on the outerperipheral side of a mounting surface of the wiring substrate. On theother hand, land parts having the NSMD structure and to which lead-outwiring parts are connected are arranged at positions overlapping withthe leads arranged on the chip loading surface of the wiring substratein transparent plan view on the inner side than the group of landshaving the land-on-through-hole structure arranged on the mountingsurface of the wiring substrate.

Further, in a semiconductor device according one embodiment, landshaving an NSMD structure and a land-on-through-hole structure arearranged in a first area not overlapping with a plurality of leadsarranged on a chip loading surface of a wiring substrate in transparentplan view on the outer peripheral side of a mounting surface of thewiring substrate. On the other hand, land parts having the NSMDstructure and to which lead-out wiring parts are connected are arrangedin a second area overlapping with the leads arranged on the chip loadingsurface of the wiring substrate in transparent plan view on the innerside than the first area of the mounting surface of the wiringsubstrate.

According to one embodiment, it is possible to improve the degree offreedom in the wiring design of a wiring substrate configuring asemiconductor device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of amounting surface of a semiconductor device ofa first embodiment.

FIG. 2 is a cross-sectional view taken along the line I-I of FIG. 1.

FIG. 3 is an enlarged cross-sectional view of an area A1 surrounded witha broken line of FIG. 2.

FIG. 4 is an enlarged plan view of main parts of a chip loading surfaceof a wiring substrate configuring the semiconductor device of FIG. 1.

FIG. 5 is an enlarged plan view of a plurality of leads arranged on thechip loading surface of FIG. 4.

FIG. 6 is a plan view shown by removing solder balls of the mountingsurface of the semiconductor device of FIG. 1.

FIG. 7 is an enlarged plan view of an area A2 surrounded with a brokenline of FIG. 6.

The left side of FIG. 8 is a plan view of a land having the SMDstructure, and the right side of FIG. 8 is a partial cross-sectionalview taken along the line II-II on the left side of FIG. 8.

The left side of FIG. 9 is a plan view of the land having the NSMDstructure, and the right side of FIG. 9 is a partial cross-sectionalview taken along the line on the left side of FIG. 9.

The left side of FIG. 10 is a plan view of the land having the NSMDstructure and the land-on-through-hole structure (land-on-viastructure), and the right side of FIG. 10 is a partial cross-sectionalview taken along the line IV-IV on the left side of FIG. 10.

FIG. 11 is a partial plan view for showing the leads of the chip loadingsurface of the wiring substrate and the lands of the mounting surface ofthe wiring substrate while being overlapped with each other.

FIG. 12 is a plan view for showing a peripheral area and a central areaof the mounting surface of the semiconductor device of FIG. 6.

FIG. 13 is a cross-sectional view taken along the line V-V of FIG. 12.

FIG. 14 is an enlarged plan view of main parts on the mounting surfaceof the wiring substrate of the semiconductor device of FIG. 12.

FIG. 15 is an enlarged plan view of main parts on the chip loadingsurface of the wiring substrate of the semiconductor device of FIG. 12.

The left side of FIG. 16 is a plan view of main parts of the landsarranged in the central area of the mounting surface of thesemiconductor device of FIG. 1, and the right side of FIG. 16 is a planview of main parts of the land arranged in the peripheral area of themounting surface of the semiconductor device of FIG. 1.

The left side of FIG. 17 is a cross-sectional view taken along the lineVI-VI on the left side of FIG. 16, and the right side of FIG. 17 is across-sectional view taken along the line VII-VII on the right side ofFIG. 16.

The left side of FIG. 18 shows a modified example of a through-holewiring and is a cross-sectional view of a part corresponding to the lineVI-VI on the left side of FIG. 16, and the right side of FIG. 18 shows amodified example of the through-hole wiring and is a cross-sectionalview of a part corresponding to the line VII-VII on the right side ofFIG. 16.

FIG. 19 is a process diagram for showing a manufacturing process of thesemiconductor device of FIG. 1.

FIG. 20 is a cross-sectional view of a wafer during a back grind processin the manufacturing process of the semiconductor device of FIG. 1.

FIG. 21 is a cross-sectional view of the wafer during a dicing processafter the process of FIG. 20.

FIG. 22 is a cross-sectional view of the chip and the wiring substrateduring a die bonding process after the process of FIG. 21.

FIG. 23 is a cross-sectional view of the chip and the wiring substrateduring a wire bonding process after the process of FIG. 22.

FIG. 24 is a cross-sectional view of the semiconductor device during acollective molding process after the process of FIG. 23.

FIG. 25 is a cross-sectional view of the semiconductor device during asolder printing process after the process of FIG. 24.

FIG. 26 is a cross-sectional view of the semiconductor device after theprocess of FIG. 25.

FIG. 27 is a cross-sectional view of the semiconductor device after areflow process after the process of FIG. 26.

FIG. 28 is a cross-sectional view of the semiconductor device during apackage dicing process after the process of FIG. 27.

FIG. 29 is a cross-sectional view of main parts of the semiconductordevice of FIG. 1 and a mother board on which the semiconductor device ismounted.

FIG. 30 is a cross-sectional view of main parts of an example of thesemiconductor device manufactured by an individual mold method and themother board on which the semiconductor device is mounted.

FIG. 31 is a cross-sectional view of main parts of the semiconductordevice of FIG. 1 and the mother board on which the semiconductor deviceis mounted.

FIG. 32 is a plan view for showing a peripheral area, a first centralarea, and a second central area on the mounting surface of thesemiconductor device of FIG. 6.

FIG. 33 is a cross-sectional view taken along the line VIII-VIII of FIG.32.

FIG. 34 is an enlarged cross-sectional view of main parts of thesemiconductor device of FIG. 33.

FIG. 35 is an enlarged plan view of main parts of the chip loadingsurface of the wiring substrate of the semiconductor device of FIG. 32.

DETAILED DESCRIPTION

The present invention will be described using the following embodimentswhile being divided into a plurality of sections or embodiments ifnecessary for convenience sake. However, except for a case especiallyspecified, the sections or embodiments are not irrelevant to each other,and one has a relationship as a part or all of a modified example,details, or a supplementary explanation of the other.

Further, when the specification refers to the number of elements(including the number of pieces, values, amounts, ranges, and the like)in the following embodiments, the number is not limited to the specificnumber, but may be smaller or larger than the specific number, exceptfor a case especially specified or a case obviously limited to thespecific number in principle.

Furthermore, it is obvious that the constitutional elements (includingelemental steps and the like) are not necessarily essential in thefollowing embodiments except for a case especially specified or a caseobviously deemed to be essential in principle.

Likewise, when the specification refers to the shapes or positionalrelationships of the constitutional elements in the followingembodiments, the present invention includes the constitutional elementsthat are substantially close or similar in shapes and the like, exceptfor a case especially specified or a case obviously deemed not to beclose or similar in principle. The same applies to the number and range.

Further, the same members are followed by the same signs in principle inall the drawings for explaining the embodiments, and the repeatedexplanation thereof will be omitted. It should be noted that hatchingswill be added in some cases even in the case of a plan view in order toeasily view the drawing.

First Embodiment <Semiconductor Device>

FIG. 1 is a plan view of a mounting surface of a semiconductor device ofthe first embodiment, FIG. 2 is a cross-sectional view taken along theline I-I of FIG. 1, and FIG. 3 is an enlarged cross-sectional view of anarea A1 surrounded with a broken line of FIG. 2. In addition, FIG. 4 isan enlarged plan view of main parts of a chip loading surface of awiring substrate configuring the semiconductor device of FIG. 1, andFIG. 5 is an enlarged plan view of a plurality of leads arranged on thechip loading surface of FIG. 4. Further, FIG. 6 is a plan view shown byremoving solder balls of the mounting surface of the semiconductordevice of FIG. 1, and FIG. 7 is an enlarged plan view of an area A2surrounded with a broken line of FIG. 6.

A semiconductor device 1 of the first embodiment is a semiconductordevice of a BGA (Ball Grid Array) package structure formed by, forexample, a MAP (Mold Array Package) method, and includes a wiringsubstrate WCB and a semiconductor chip (hereinafter, simply referred toas a chip) CHP mounted on a chip mounting area that is located nearly atthe center of a chip loading surface of the wiring substrate WCB.

The wiring substrate WCB is a structure in which wirings for extractingan electrode of an integrated circuit of a chip CHP to the outside areformed. For example, the wiring substrate WCB is formed in aquadrangular shape in plan view, and the external dimension thereof isset to be, for example, 20×20 mm or larger, specifically, 25×25 mm.

A substrate SB configuring the wiring substrate WCB is formed by using,for example, an insulating thin plate formed in a quadrangular shape inplan view, and has a chip loading surface (first surface), a mountingsurface (second surface) on the opposite side, and a plurality ofinsulating layers IF laminated therebetween. Each insulating layer IF isformed of, for example, epoxy resin. It should be noted that thequadrangular shape of the wiring substrate WCB (or the substrate SB)includes a polygonal shape or a quadrangular shape with rounded cornersby forming a taper or the like at each corner of the wiring substrateWCB (or the substrate SB).

As shown in FIGS. 3 and 4, a plurality of leads (bonding fingers andbonding leads) LA, a plurality of through-hole lands TLA, and aplurality of wiring parts WA through which these are electricallyconnected with each other are arranged on the chip loading surface ofthe substrate SB. The leads LA, the through-hole lands TLA, and thewiring parts WA are integrally formed by using, for example, metal suchas copper (Cu) or the like.

The leads LA are arranged side by side along the outer periphery of thechip CHP so as to surround the chip CHP. Here, as shown in FIG. 4, theleads LA are arranged along the outer periphery (four sides) of the chipCHP in a state where, for example, two rows of leads are arranged. Thetwo rows of leads LA (LA1 and LA2) are arranged in a zigzag manner whilebeing separated from each other. That is, the two rows of leads LA (LA1and LA2) are arranged in a state where the positions thereof are shiftedalong the outer periphery of the chip CHP. As shown in FIG. 5, the widthLw of each lead LA is, for example, about 85 μm. The minimum distance Ldbetween the leads LA is, for example, about 50 μm. The minimum pitch Lpof the lead LA is, for example, about 370 μm.

As shown in FIG. 4, the through-hole land TLA is formed in asubstantially circular pattern in plan view while having a width widerthan each of the leads LA and the wiring parts WA. The diameter of thethrough-hole land TLA is, for example, about 300 μm, and the minimumpitch of the through-hole land TLA is, for example, about 370 μm.

Further, a solder resist (first insulating film) SR1 is formed on thechip loading surface of the substrate SB so as to cover the through-holelands TLA and the wiring parts WA. The solder resist SR1 is formed of,for example, mixed resin of epoxy resin and acrylic resin. As shown inFIG. 4, an opening portion KA from which some of the wiring parts WA areexposed is formed at a part of the solder resist SR1. Some of the wiringparts WA exposed from the opening portion KA are the leads LA. It shouldbe noted that the solder resist SRI is hatched in FIG. 4 in order toeasily view the drawing.

Further, as shown in FIGS. 2 and 3, the chip CHP is mounted on the chiploading surface of the substrate SB (wiring substrate WCB) through a diebond material DB and the solder resist SR1 in a state where the mainsurface (third surface) of the chip CHP faces upwards and the backsurface (fourth surface) of the chip CHP faces the chip loading surfaceof the substrate SB. It should be noted that the die bond material DB isformed of, for example, a paste material, a film material, or the like.

For example, the chip CHP is formed in a quadrangular shape in planview, and the external dimension thereof is set to be, for example,about 7×7 mm. As shown in FIG. 4, a plurality of pads (electrodes) PD isarranged side by side along the outer periphery (four sides) of the chipCHP in the vicinity of the outer periphery (four sides) of the mainsurface of the chip CHP. The pads PD are electrically connected with theintegrated circuit of the chip CHP, and are electrically connected withthe leads LA of the wiring substrate WCB through bonding wires(hereinafter, simply referred to as wires) BW as shown in FIG. 3.

Further, as shown in FIG. 3, a resin sealing body MD is formed on thechip loading surface of the substrate SB so as to cover the chip CHP,the wires BW, the leads LA, and the solder resists SRI. The resinsealing body MD is formed of, for example, thermosetting epoxy resin.The side surfaces of the resin sealing body MD coincide with the sidesurfaces of the wiring substrate WCB, and are formed nearlyperpendicular to the chip loading surface of the wiring substrate WCB.

On the other hand, as shown in FIGS. 3 and 6, a plurality of lands (bumplands, pads, and terminals) LD (LD1, LD2, and LD3), a plurality ofthrough-hole lands TLB, and the wiring parts WB are arranged on themounting surface of the substrate SB. The lands LD (LD1, LD2, and LD3),the through-hole lands TLB, and the wiring parts WB are formed of, forexample, metal such as copper (Cu) or the like.

The lands (first lands) LD1 are arranged along the outer periphery (foursides: edge) of the substrate SB in a state where, for example, two rowsof lands LD1 are arranged. Further, the inner lands (second lands) LD2and LD3 surrounded by the group of lands LD1 are also arranged along theouter periphery (four sides: edge) of the substrate SB in a state wheretwo rows of lands LD2 and two rows of lands LD3 are arranged. A distance(shortest distance) between the group of lands LD1 and the group oflands LD2 and a distance (shortest distance) between the group of landsLD2 and the group of lands LD3 are set to be equal to or larger than onerow (corresponding to one land LD) of lands LD. Accordingly, it ispossible to easily route the wires on the mother board side on which thesemiconductor device 1 is mounted.

Each of the lands LD (LD1 to LD3) is formed in, for example, a circularshape in plan view, and the diameter thereof is, for example, about 400μm. Further, as shown in FIG. 7, the pitch Dp between the adjacent landsLD (LD1 to LD3) is, for example, about 800 μm.

Further, as shown in FIGS. 2 and 3, solder balls (solder bumps, externalterminals, and projecting electrodes) BE are bonded to the respectivelands LD (LD1 to LD3). The solder ball BE is formed of, for example, alead-free alloy such as a tin (Sn)—silver (Ag)—copper (Cu) alloy or thelike.

As shown in FIG. 3, the through-hole land TLB is arranged in the chiploading area. The through-hole land TLB is formed in a substantiallycircular pattern having a width larger than that of the wiring part WBand a diameter smaller than that of the land LD (LD1 to LD3). Thediameter of the through-hole land TLB is, for example, about 300 μm, andthe minimum pitch between the adjacent through-hole lands TLB is, forexample, about 370 μm.

The wiring part WB is a lead-out wiring part that electrically connectseach of the lands LD2 and LD3 to the through-hole land TLB, and isintegrally formed with the lands LD2 and the LD3 and the through-holeland TLB. The width of the wiring part WB is, for example, about 300 μm.

Further, a solder resist (second insulating film) SR2 is formed on themounting surface of the substrate SB so as to cover a part of the wiringpart WB and the through-hole land TLB. The solder resist SR2 is formedof, for example, mixed resin of epoxy resin and acrylic resin. Aplurality of opening portions KB for exposing the lands LD (LD1 to LD3)and a part of the wiring part WB is formed in a part of the solderresist SR2.

The opening portion KB is formed in a circular shape having a diameterlarger than that of the land LD (LD1 to LD3) in plan view, and isarranged so as to include the entirety of each land LD (LD1 to LD3).That is, all the lands LD of the mounting surface of the semiconductordevice 1 in the embodiment are lands LD having an NSMD (Non Solder MaskDefined) structure. The diameter of the opening portion KB is, forexample, about 520 μm. The land structure will be described later.

Further, as shown in FIGS. 2 and 3, a plurality of wiring layers isformed between the chip loading surface and the mounting surface of thesubstrate SB, and an inner-layer wiring WI is formed in each of thewiring layers. The inner-layer wiring WI is formed of, for example,metal such as copper (Cu) or the like. The number of wiring layers is,for example, 2, 4, or more. It should be noted that the substrate SBcorresponds to a core material in the case of a two-layer substratehaving two wiring layers, and corresponds to the assembly of all theinsulating layers IF sandwiched between the solder resists SR1 and SR2in the case of a multilayer substrate having four or more wiring layers.That is, the “substrate” mentioned here is configured using theinsulating layers IF.

Further, as shown in FIG. 3, a plurality of through-holes TH (TH1 andTH2) penetrating the chip loading surface and the mounting surfacelocated on the back side thereof is formed in the substrate SB whilebeing nearly perpendicular to the chip loading surface and the mountingsurface. Through-hole wirings WT (WT1 and WT2) are provided inside thethrough-holes TH (TH1 and TH2), respectively. The diameter of eachthrough-hole TH (TH1 and TH2) is, for example, about 150 μm.

One through-hole (first through-hole) TH1 is arranged at a positionoverlapping with the through-hole land TLA on the outer peripheral sideof the chip loading surface of the substrate SB and the land LD1 on theouter peripheral side of the mounting surface of the substrate SB inplan view. Accordingly, the through-hole land TLA on the outerperipheral side of the chip loading surface of the substrate SB and theland LD1 on the outer peripheral side of the mounting surface of thesubstrate SB are electrically connected with each other through thethrough-hole wiring (first through-hole wiring) WT1. That is, thethrough-hole land TLA on the outer peripheral side of the chip loadingsurface of the substrate SB is directly and electrically connected withthe land LD1 on the outer peripheral side of the mounting surface of thesubstrate SB through the through-hole wiring WT1.

The other through-hole (second through-hole) TH2 is arranged at aposition overlapping with the through-hole land TLA arranged on thecentral side (in the chip loading area) of the chip loading surface ofthe substrate SB and the through-hole land TLB arranged on the centralside (in the chip loading area) of the mounting surface of the substrateSB in plan view. Accordingly, the through-hole land TLA arranged on thecentral side (in the chip loading area) of the chip loading surface ofthe substrate SB and the through-hole land TLB arranged on the centralside (in the chip loading area) of the mounting surface of the substrateSB are electrically connected with each other through the through-holewiring (second through-hole wiring) WT2. That is, the through-hole landTLA of the chip loading surface of the substrate SB is electricallyconnected with the through-hole land TLB of the mounting surface of thesubstrate SB through the through-hole wiring WT2, and is furtherelectrically connected with the lands LD2 and LD3 via the wiring part WBformed (connected) integrally with the through-hole land TLB.

Next, problems found by the inventors about the land structure arrangedon the mounting surface of the semiconductor device will be described.

The left side of FIG. 8 is a plan view of the land having the SMDstructure, and the right side of FIG. 8 is a partial cross-sectionalview taken along the line II-II on the left side of FIG. 8. In the caseof the SMD (Solder Mask Defined) structure, the diameter of an openingportion KC formed in the solder resist SR2 is smaller than that of theland LD, and the opening portion KC is included in the upper surface(the surface facing the mother board) of the land LD. Therefore, theentire circumference near the outer periphery of the upper surface ofthe land LD is covered with the solder resist SR2. In this case, thecontact surface between the solder ball BE and the land LD is flat(linear), and the bonding area between the solder ball BE and the landLD is smaller than the land LD having the NSMD structure. Therefore, ina test accompanied by heat such as a temperature cycle test or the like,cracks CK are likely to be generated in the solder ball BE near theinner periphery of the opening portion KC of the solder resist SR2. Thatis, in the case of the SMD structure, there is a problem that thebonding reliability between the solder ball BE and the land LD isdeteriorated.

On the other hand, the left side of FIG. 9 is a plan view of the landhaving the MSMD structure, and the right side of FIG. 9 is a partialcross-sectional view taken along the line on the left side of FIG. 9. Inthe case of the NSMD structure, the diameter of the opening portion KBformed in the solder resist SR2 is larger than that of the land LD, andthe opening portion KB includes the land LD. Therefore, in the case ofthe NSMD structure, the upper surface of the land LD and the sidesurface intersecting therewith are exposed from the opening portion KBof the solder resist SR2. Therefore, since the solder ball BE is bondedto the upper surface and the side surface of the land LD, the land LDhaving the NSMD structure is higher than the land LD having the SMDstructure in the bonding reliability between the solder ball BE and theland LD. However, even in the case of the NSMD structure, the wiringpart WB extending outward from a part of the outer periphery of the landLD exists, and the outer periphery of the opening portion KB overlapswith the wiring part WB. Therefore, in a test accompanied by heat suchas a temperature cycle test or the like, the stress concentrates on thewiring part WB with which the outer periphery of the opening portion KBoverlaps, and the cracks CK are generated in the solder ball BE. Thatis, even in the case of the NSMD structure, there is a problem that thebonding reliability between the solder ball BE and the land LD isdeteriorated in the case where the lead-out wiring part is connected.According to the study by the inventors, even in the case of using theland having the NSMD structure, when the lead-out wiring part isconnected with the land, the problem that the cracks CK are generated inthe solder ball BE on the outer peripheral side of the wiring substrateWCB where the thermal stress is relatively high becomes remarkable, forexample, when the external dimension of the wiring substrate WCB is setto be 20×20 mm or larger.

Next, the left side of FIG. 10 is a plan view of the land having theMSMD structure and the land-on-through-hole structure (land-on-viastructure), and the right side of FIG. 10 is a partial cross-sectionalview taken along the line IV-IV on the left side of FIG. 10. The land ofthe first embodiment has the land-on-through-hole structure (land-on-viastructure) and the NSMD structure. That is, the diameter of the openingportion KB formed in the solder resist SR2 is larger than that of theland LD, and the opening portion KB is arranged while including the landLD. However, in the case of the land-on-through-hole structure, thethrough-hole TH overlaps with the land LD in plan view, and there is nowiring part connected to the land LD in the same layer as the land LD.Therefore, since the solder ball BE is bonded to the upper surface andthe side surface of the entire circumference of the land LD, the bondingstrength of the solder ball BE is improved, and cracks are hardlygenerated in the solder ball BE. Therefore, the land-on-through-holestructure is the most excellent in thermal stress resistance in theabove-described land structures.

However, according to the study, the inventors found that when theland-on-through-hole structure was adopted for all the lands LD in themounting surface of the wiring substrate WCB, it was difficult to routethe wirings connecting the leads LA arranged on the chip loading surfaceof the wiring substrate WCB to the lands LD arranged on the mountingsurface of the wiring substrate WCB. FIG. 11 is a partial plan view forshowing the leads of the chip loading surface of the wiring substrateand the lands of the mounting surface of the wiring substrate whilebeing overlapped with each other. Since the wires BW (see FIG. 3) areconnected with the leads LA, the leads LA are formed in accordance withthe dimension (the pitch or the adjacent distance) of the pad PD of thechip CHP. Therefore, the leads LA are densely arranged at narrowadjacent distances. On the other hand, the lands LD cannot be made toosmall from the viewpoint of securing the bonding reliability with thesolder balls BE, and cannot be arranged at narrower distances from theviewpoint of being connected with the lands (the terminals and theelectrodes) of the mother board. Thus, if the land LD having theland-on-through-hole structure is arranged in the area (the overlappedarea in transparent plan view) where the lead LA is arranged, it isdifficult to arrange the lead LA and it is difficult to route the wiringconnecting the lead LA with the land LD. Therefore, it is difficult todesign the layout of the wirings of the wiring substrate WCB, and ittakes time to develop the wiring substrate WCB. In addition, the cost ofthe semiconductor device 1 is increased. Further, it is difficult to layout the wirings, and thus there is a case that the wiring substrate WCBis increased in size.

Accordingly, in the semiconductor device 1 of the embodiment, as shownin FIG. 3 and the like, the NSMD structure and the land-on-through-holestructure in which the lead-out wiring part is not connected with theland LD1 are adopted for each land LD1 arranged at a position notoverlapping with the lead LA in transparent plan view on the outerperipheral side of the mounting surface of the wiring substrate WCB. Onthe other hand, not the land-on-through-hole structure but the NSMDstructure and the land structure in which the lead-out wiring part WB isconnected are adopted for each land LD2 overlapping with the lead LA intransparent plan view on the central side of the mounting surface of thewiring substrate WCB.

Specifically, the above-described structures are shown, for example, inthe following manners. FIG. 12 is a plan view for showing a peripheralarea and a central area of the mounting surface of the semiconductordevice of FIG. 6, FIG. 13 is a cross-sectional view taken along the lineV-V of FIG. 12, FIG. 14 is an enlarged plan view of main parts on themounting surface of the wiring substrate of the semiconductor device ofFIG. 12, and FIG. 15 is an enlarged plan view of main parts on the chiploading surface of the wiring substrate of the semiconductor device ofFIG. 12. It should be noted that the chip CHP and the leads LA arrangedon the mounting surface of the wiring substrate WCB are also shown in atransparent manner in FIG. 12. In addition, the solder resist SR1 ishatched in FIG. 15 in order to easily view the drawing.

In the first embodiment, as shown in FIGS. 12 and 13, the mountingsurface of the wiring substrate WCB is divided into a peripheral area(first area) PA and a central area (second area) CA inside theperipheral area in the layout design of the wirings. It should be notedthat the peripheral area PA and the central area CA are hatched in FIG.12 in order to easily view the drawing.

The peripheral area PA is an area where the lands having the NSMDstructure and the land-on-through-hole structure in which the lead-outwiring parts WB are not connected are arranged, and is arranged to havea width from the outer periphery of the wiring substrate WCB toward thecenter. The leads LA arranged in the chip loading surface of the wiringsubstrate WCB are arranged at positions not overlapping with theperipheral area PA in transparent plan view. That is, the leads LAarranged in the chip loading surface of the wiring substrate WCB do notoverlap with the lands LD1 arranged on the outer peripheral side of themounting surface of the wiring substrate WCB in transparent plan view.It should be noted that a concrete example of the lands having theland-on-through-hole structure arranged in the peripheral area PA willbe described later.

On the other hand, the central area CA is an area where the lands havingthe NSMD structure and to which the lead-out wiring parts are connectedare arranged, and is arranged on the inner side than the peripheral areaPA while being surrounded by the peripheral area PA. The leads LA in thechip loading surface of the wiring substrate WCB are arranged atpositions overlapping with the central area CA in transparent plan view.That is, the leads LA arranged in the chip loading surface of the wiringsubstrate WCB overlap with the lands LD2 arranged on the central side ofthe mounting surface of the wiring substrate WCB in transparent planview. A concrete example of the lands having the NSMD structure arrangedin the central area CA and to which the lead-out wiring parts areconnected will be described later.

Further, as shown in FIGS. 12 to 15, an empty area FA is arrangedbetween the peripheral area PA and the central area CA. The empty areaFA does not belong to either the peripheral area PA or the central areaCA. The distance (the shortest distance between the inner periphery ofthe peripheral area PA and the outer periphery of the central area CA:third distance) Fd of the empty area FA is larger than the diameter ofthe land LD (LD1 and LD 2).

Further, the distance Fd of the empty area FA is larger than thedistance Dd (the distance Dd1 between the lands LD1 arranged along theedge of the wiring substrate WCB, or the distance Dd2 between the landsLD2 arranged along the edge of the wiring substrate WCB) between thelands LD. It should be noted that the distances Dd1 and Dd2 are equal.

Further, the distance Fd of the empty area FA is larger than theadjacent pitch Dp (the adjacent pitch Dp1 between the lands LD1 arrangedalong the edge of the wiring substrate WCB, or the adjacent pitch Dp2between the lands LD2 arranged along the edge of the wiring substrateWCB) between the lands LD. It should be noted that the adjacent pitchesDp1 and Dp2 are equal.

Further, for example, there are different points of view as follows inthe following manners. That is, the distance (first distance) Dsdbetween the lands (the first reference land and the second referenceland) LD1 and LD2 arranged adjacent to each other at the closestpositions among the lands LD1 and LD2 is larger than the distance Dd(the distance Dd1 between two lands LD1 adjacent along the outerperipheral direction of the wiring substrate WCB, or the distance Dd2between two lands LD2 adjacent along the outer peripheral direction ofthe wiring substrate WCB) between the lands LD.

Further, the distance Dsd between the lands LD1 and LD2 is larger thanthe diameter of each land LD (LD1 and LD2). Further, the distance Dsdbetween the lands LD1 and LD2 is larger than the adjacent pitch Dp (theadjacent pitch Dp1 between two lands LD1 adjacent along the outerperipheral direction of the wiring substrate WCB, or the adjacent pitchDp2 between two lands LD2 adjacent along the outer peripheral directionof the wiring substrate WCB) between the lands LD.

Here, the outer peripheral position (range setting) of the central areaCA will be described with reference to FIG. 15. As described above, ifthe land LD1 (see FIG. 14) having the land-on-through-hole structure isarranged at a position overlapping with the lead LA in transparent planview, it is difficult to route the wirings. From this viewpoint, it isconceivable that the land LD1 having the land-on-through-hole structuremay be arranged at a position not overlapping with the lead LA intransparent plan view, that is, on the outer side (the outer peripheralside of the wiring substrate WCB: the right side of FIG. 15) than thelead LA1 (LA). Actually, however, the wiring parts WA on the outer sidethan the leads LA1 are also densely arranged. If the land LD1 having theland-on-through-hole structure is arranged while overlapping with thedense area of the wiring parts WA in transparent plan view, it isdifficult to route the wirings of the wiring substrate WCB as similar tothe arrangement area of the leads LA.

Accordingly, in the embodiment, the central area CA is extended to apartof the arrangement area of the wiring parts WA on the outer side thanthe leads LA1. That is, the outer peripheral position of the centralarea CA is set at the position X2 obtained by adding the length Rc2 tothe length Rc1 from the center position X0 of the chip CHP to theposition X1 of the outermost end of the lead LA1. The length Rc2 isequal to or larger than, for example, the diameter of each land LD (LD1and LD2). The condition of the length Rc2 can be set to the same lengthcondition as described for the distance Fd. By configuring as describedabove, the dense area of the wiring parts WA on the outer side than theleads LA1 can be also used as the arrangement area of the lands LD2 andLD3 having the NSMD structure and to which the lead-out wiring parts areconnected. Thus, the wirings of the wiring substrate WCB can be easilyrouted.

On the other hand, for the same reason as described above, if theperipheral area PA (that is, the area where the land LD1 having theland-on-through-hole structure is arranged) enters the dense area of thewiring parts WA on the chip loading surface side of the wiring substrateWCB, it is difficult to route the wirings of the wiring substrate WCB.

Therefore, in the embodiment, the inner periphery of the peripheral areaPA is defined so as to be arranged at the position X3 that is apart fromthe position X2 of the outer periphery of the central area CA only bythe distance Fd. That is, the peripheral area PA is set at the positionX3 obtained by subtracting the distance Fd from the length Rc3 from theposition X4 of the outer periphery of the wiring substrate WCB to theposition X2 of the outer periphery of the central area CA. Byconfiguring as described above, the land LD1 having theland-on-through-hole structure is not arranged in the dense area of thewiring parts WA on the outer side than the leads LA. Thus, the wiringsof the wiring substrate WCB can be easily routed. It should be notedthat the center of the chip CHP is used as a reference when setting theboundary (the outer periphery and the inner periphery) positions of theperipheral area PA and the central area CA in the above example.However, the present invention is not limited thereto. For example, theposition of the center of the wiring substrate WCB, the position of theouter periphery of the wiring substrate WCB, or the already-determinedboundary position of the peripheral area PA or the central area CA maybe used as a reference.

Next, a structural example of the lands LD (LD1 to LD3) arranged in thecentral area CA and the peripheral area PA of the mounting surface ofthe semiconductor device 1 in the first embodiment will be described.The left side of FIG. 16 is a plan view of main parts of the landsarranged in the central area of the mounting surface of thesemiconductor device, the right side of FIG. 16 is a plan view of mainparts of the land arranged in the peripheral area of the mountingsurface of the semiconductor device, the left side of FIG. 17 is across-sectional view taken along the line VI-VI on the left side of FIG.16, and the right side of FIG. 17 is a cross-sectional view taken alongthe line VII-VII on the right side of FIG. 16. It should be noted thatthe solder resist SR2 is hatched in FIG. 16 in order to easily view thedrawing.

As shown on the left sides of FIGS. 16 and 17, the lands LD2 and LD3having the NSMD structure and to which the lead-out wiring parts WB areconnected are arranged in the central area CA of the wiring substrateWCB of the semiconductor device 1. That is, an opening portion (secondopening portion) KB2 (KB) having a diameter larger than the lands LD2and LD3 and including the lands LD2 and LD3 is formed in the solderresist SR2. In addition, the lands LD2 and LD3 and a part of the wiringpart WB connected thereto are exposed from the opening portion KB2. Thediameter of the opening portion KB2 is the same as the opening portionsKB and KB1.

The lands LD2 and LD3 are electrically connected with the through-holeland TLB formed on the mounting surface of the substrate SB through thelead-out wiring part WB formed on the mounting surface of the substrateSB. The through-hole land TLB is electrically connected with thethrough-hole land TLA formed on the chip loading surface of thesubstrate SB through the through-hole wirings WT2. Each of thethrough-hole wirings WT2 is formed in the entire inner wall surface of athrough-hole TH2 drilled in the substrate SB while being covered with aconductive film such as copper (Cu) or the like. An insulating film Fiis filled inside the conductive film for the through-hole wiring WT2 inthe through-hole TH2. The insulating film Fi is formed of, for example,resin.

As described above, the lands LD having the NSMD structure and to whichthe lead-out wiring parts WB are connected are arranged in the centralarea CA of the wiring substrate WCB. Thus, the leads LA and the lands LDcan be satisfactorily connected with each other without confusing therouting of the wirings. Therefore, it is possible to improve the degreeof freedom of the wiring design of the wiring substrate WCB wherehigh-density wirings are arranged. Therefore, it is possible to shortenthe development period of the semiconductor device 1. Further, since thewirings of the wiring substrate WCB can be densely arranged, it ispossible to promote miniaturization of the semiconductor device 1.Further, the cost of the semiconductor device 1 can be reduced.

Next, as shown on the right sides of FIGS. 16 and 17, the land LD1having the NSMD structure and the land-on-through-hole structure inwhich the lead-out wiring part WB is not connected with the land isarranged in the peripheral area PA of the wiring substrate WCB of thesemiconductor device 1. That is, the opening portion (first openingportion) KB1 (KB) having a diameter larger than the land LD1 andincluding the land LD1 is formed in the solder resist SR2. Since thelead-out wiring part WB is not connected with the land LD1, the uppersurface and the entire side surface of land LD1 are exposed from openingportion KB1.

Further, the land LD1 formed on the mounting surface of the substrate SBis electrically connected with the through-hole land TLA formed on thechip loading surface of the substrate SB through the through-holewirings WT1. Each of the through-hole wirings WT1 is also formed in theentire inner wall surface of a through-hole TH1 drilled in the substrateSB while being covered with a conductive film such as copper (Cu) or thelike. Further, in this case, the insulating film Fi formed of resin orthe like is also filled inside the conductive film for the through-holewiring WT1 in the through-hole TH1.

As described above, the land LD1 having the NSMD structure and theland-on-through-hole structure in which the lead-out wiring part WB isnot connected is arranged in the peripheral area PA whererelatively-large thermal stress is applied in the wiring substrate WCB.Accordingly, it is possible to improve the bonding strength between theland LD1 and the solder ball BE on the outer peripheral side of themounting surface of the wiring substrate WCB, and thus the occurrence ofthe cracks in the solder ball BE can be suppressed or prevented.Therefore, the connecting reliability between the semiconductor device 1and the mother board can be improved.

However, the structure of the through-hole wiring WT is not limited tothe above-described one. The left side of FIG. 18 shows a modifiedexample of the through-hole wiring, and is a cross-sectional view of apart corresponding to the line VI-VI on the left side of FIG. 16. Theright side of FIG. 18 shows a modified example of the through-holewiring, and is a cross-sectional view of a part corresponding to theline VII-VII on the right side of FIG. 16. Here, the through-holes TH1and TH2 are filled with not the insulating films Fi but, for example,metal films such as copper (Cu) or the like. That is, the through-holewirings WT1 and WT2 in FIG. 18 are formed by embedding only the metalfilms into the through-holes TH1 and TH2.

<Manufacturing Method of Semiconductor Device>

Next, an example of a MAP method (collective molding method) formanufacturing the semiconductor device 1 of the first embodiment will bedescribed with reference to FIGS. 20 to 28 along the process diagram ofFIG. 19.

1. Back Grind

First, the back surface of a semiconductor wafer (hereinafter, simplyreferred to as a wafer WF) having a chip area where an integratedcircuit is formed by forming an integrated circuit element such as atransistor (MISFET (Metal Insulator Semiconductor Field EffectTransistor)) or the like and a multilayer wiring by using an ordinarysemiconductor manufacturing technique is ground (back grind: S101 inFIG. 19) as shown in FIG. 20. That is, after the element formationsurface (top surface) of the wafer WF is covered with a protection tapePT, the wafer WF is arranged on a stage while allowing the back surfaceon the opposite side of the element formation surface (top surface) ofthe wafer WF to face upward. Next, the back surface of the wafer WF isground by a grinder G to reduce the thickness of the wafer WF.Accordingly, the wafer WF is ground.

2. Wafer Dicing

Thereafter, as shown in FIG. 21, the wafer WF is diced to be dividedinto chips (S102 in FIG. 19). That is, first, a dicing tape DT isallowed to adhere to a concentric dicing frame DFM, and then the waferWF is arranged on the dicing tape DT. Next, the wafer WF is cut along adicing line by using dicing blade DS that rotate, so that the wafer WFis divided into chips.

3. Die Bonding

Next, as shown in FIG. 22, the divided chips CHP are mounted on thewiring substrate WCB (die bonding: S103 in FIG. 19). That is, after eachchip CHP is adsorbed by a collet C1, the chips CHP are mounted on thewiring substrate WCB through a die bond material DB. At this time, thewiring substrate WCB is integrated so as to form a plurality ofsemiconductor devices, and each chip CHP is mounted in the area whereeach semiconductor device is obtained. Thereafter, heat treatment(baking) is performed to increase the adhesion strength between thechips CHP and the wiring substrate WCB.

4. Plasma Cleaning

Next, plasma cleaning is performed on the surface (chip loading surface)of the wiring substrate WCB on which the chips CHP are mounted (S104 inFIG. 19). The plasma cleaning is performed for the purpose of improvingthe adhesion between resin and the wiring substrate WCB in thesubsequent molding process. It should be noted that in the case whereresin that is excellent (high) in adhesion to the wiring substrate WCBis used, the plasma cleaning process may be omitted.

5. Wire Bonding

Thereafter, as shown in FIG. 23, the leads formed on the wiringsubstrate WCB and the pads of the chips CHP are connected with eachother by the wires BW made of, for example, gold (S105 in FIG. 19).Specifically, after the wire BW is first bonded to the pad of the chipCHP with a capillary C2, the capillary C2 is moved, so that the wire BWis second bonded to the lead of the wiring substrate WCB. Accordingly,the leads of the wiring substrate WCB and the pads of the chips CHP areelectrically connected with each other by the wires BW. It should benoted that the wires BW to be used may be wires made of materialcontaining not gold (Au) but copper (Cu) as a main component.

6. Mold

Next, as shown in FIG. 24, the entire chip loading surface of the wiringsubstrate WCB is sealed with resin M (S106 in FIG. 19). Specifically,the wiring substrate WCB on which the chips CHP are mounted issandwiched between an upper mold UK and a lower mold BK from the upperand lower directions so that the chips CHP mounted on the wiringsubstrate WCB are located in one cavity (recess) formed in the lowermold BK, and the resin M is poured from an insertion opening into themold space of the lower mold BK. Accordingly, the chips CHP on thewiring substrate WCB are collectively sealed with the resin M.Thereafter, in order to cure the resin M, heat treatment (baking) isperformed for the wiring substrate WCB. It should be noted that insteadof the lower mold BK, a molding die provided in the upper mold UK may beused as the above-described cavity.

7. Solder Printing

Next, as shown in FIG. 25, a solder paste SP is applied to the backsurface of the wiring substrate WCB by means of solder printing (S107 inFIG. 19). Specifically, a metal mask MSK is arranged on the back surfaceof the wiring substrate WCB, and the solder paste SP is printed on themetal mask MSK with a squeegee S1. Accordingly, as shown in FIG. 26, thesolder pastes SP are formed on the lands LD (lands LD1 to LD3: see FIG.3 and the like) of the wiring substrate WCB. Thereafter, as shown inFIG. 27, the solder pastes SP formed on the back surface of the wiringsubstrate WCB are made into the hemispherical solder balls BE byreflowing the wiring substrate WCB. As described above, externalconnection terminals configured using the solder balls BE are formed onthe back surface of the wiring substrate WCB. It should be noted thatthe method of forming the external connection terminals (solder ballsBE) is not limited to the above-described solder printing method, but aso-called ball supply method in which the solder balls formed in aspherical shape are supplied onto the lands and are melted by heating tobe connected with the lands may be adopted.

8. Package Dicing

Thereafter, as shown in FIG. 28, the wiring substrate WCB is diced(package dicing: S108 in FIG. 19). That is, first, after the dicing tapeDT is allowed to adhere to the concentric dicing frame DFM, the wiringsubstrate WCB after the collective molding is arranged on the dicingtape DT. Next, each semiconductor device 1 is obtained by cutting thewiring substrate WCB using the dicing blades DS that rotate at highspeed. As described above, the semiconductor device 1 having the BGApackage structure shown in FIG. 1, FIG. 2, and the like can bemanufactured. The chip loading surface of the wiring substrate WCB ofthe semiconductor device 1 is sealed with the resin sealing body MDconfigured using the resin M. On the other hand, the external connectionterminals configured using the solder balls BE are formed on themounting surface on the opposite side of the chip loading surface of thewiring substrate WCB. Thereafter, the semiconductor device 1 having theBGA package structure is housed and shipped.

<Example of Mounting Structure of Semiconductor Device>

Next, a mounting example of the semiconductor device 1 manufactured asdescribed above will be described with reference to FIG. 29. FIG. 29 isa cross-sectional view of main parts of the semiconductor device of FIG.1 and the mother board on which the semiconductor device is mounted.

First, a solder paste (welding solder) is formed on a land MLD formed ona mother board MCB. The land structure on the mother board MCB side has,for example, the SMD structure shown in FIG. 8. That is, an openingportion KC smaller than the diameter of the land MLD of the mother boardMCB is formed in a solder resist SR3 formed on the device loadingsurface of the mother board MCB while being included in the land MLD.

Next, the solder ball BE of the mounting surface of the semiconductordevice 1 and the land MLD of the mother board MCB are connected witheach other through a solder paste in a state where the mounting surfaceof the semiconductor device 1 faces the mother board MCB. Thereafter,the solder ball BE of the semiconductor device 1 and the solder paste onthe land MLD of the mother board MCB are integrated by reflowing (heattreatment) the mother board MCB and the semiconductor device 1, so thatthe semiconductor device 1 is mounted on the mother board MCB.

After such a mounting process, a temperature cycle test or the like isconducted for the semiconductor device 1. The temperature cycle test isconducted under the conditions of, for example, 2000 cycles in the rangeof −55° C. (or −40° C.) to 125° C. At this time, theland-on-through-hole structure is adopted for the land structure on theouter peripheral side of the mounting surface of the semiconductordevice 1 where the thermal stress is relatively large in thesemiconductor device 1 of the embodiment, and thus the present inventioncan sufficiently cope with the temperature environment of temperaturecycle test. That is, since the cracks of the solder ball BE on the outerperipheral side of the mounting surface of the semiconductor device 1can be suppressed or prevented in the semiconductor device 1 of thefirst embodiment, the bonding strength between the solder ball BE of thesemiconductor device 1 and the land MLD of the mother board MCB can beimproved. Therefore, the yield of the semiconductor device 1 can beimproved.

Further, as described above, a space is provided between the land LD1and the land LD2 and between the land LD2 and the land LD3 of themounting surface of the semiconductor device 1 in the embodiment.Therefore, the wiring part WD connected with the land MLD of the motherboard MCB can be extracted to an area (position) facing the distancesbetween the land LD1 and the land LD2 and between the land LD2 and theland LD3 of the semiconductor device 1 in the mother board MCB.Therefore, the degree of freedom of routing the wirings on the motherboard MCB side can be improved. Here, a through-hole MTH orthogonal tothe upper and lower surfaces of the mother board MCB and a through-holewiring MWT formed therein are arranged in the area (position) facing thedistances between the land LD1 and the land LD2 and between the land LD2and the land LD3 of the semiconductor device 1 in the mother board MCB.

Here, the configuration of the first embodiment can be also applied to asemiconductor device manufactured by, for example, an individual moldmethod. However, as shown in FIG. 30, in the case where a resin sealingbody MD0 is not formed up to the outer solder balls BE in the mountingsurface of the wiring substrate WCB of the semiconductor device 1 in theindividual mold method, the stress applied to the outer peripheral sideof the wiring substrate WCB at the time of the temperature cycle test orthe like is smaller than that of a semiconductor device manufactured bya MAP mold method. In the case of the semiconductor device manufacturedby the individual mold method shown in FIG. 30, even if thermal stressis applied to the outer peripheral side of the wiring substrate WCB,there is an escape place as indicated by an arrow P1 against the thermalstress. On the other hand, in the semiconductor device 1 manufactured bythe MAP mold method shown in FIG. 31, since the entire area of the chiploading surface of the wiring substrate WCB is covered with the resinsealing body MD, the escape against the thermal stress is small and thethermal stress concentrates on the solder balls BE. Thus, theconfiguration of the first embodiment can be also applied to thesemiconductor device manufactured by the individual mold method, butexhibits an effect particularly in the semiconductor device 1manufactured by the MAP mold method.

Further, the configuration of the first embodiment can be also appliedto a semiconductor device having, for example, an LGA (Land Grid Array)package structure. In the case of the LGA, the surface of the land LD iscovered with a solder material thinner than the solder ball. However,the bonding defect of the solder ball is a serious problem particularlyin the semiconductor device having the BGA package structure. Therefore,the configuration of the first embodiment can be also applied to thesemiconductor device having the LGA package structure, but exhibits aneffect particularly in the semiconductor device having the BGA packagestructure.

Second Embodiment

FIG. 32 is a plan view for showing a peripheral area, a first centralarea, and a second central area on the mounting surface of thesemiconductor device of FIG. 6, FIG. 33 is a cross-sectional view takenalong the line VIII-VIII of FIG. 32, FIG. 34 is an enlargedcross-sectional view of main parts of the semiconductor device of FIG.33, and FIG. 35 is an enlarged plan view of main parts of the chiploading surface of the wiring substrate of the semiconductor device ofFIG. 32.

In the second embodiment, as shown in FIGS. 32 and 33, the mountingsurface of a wiring substrate WCB is divided into a peripheral area(first area) PA, a first central area (second area) CA1 inside theperipheral area, and a second central area (third area) CA2 inside thefirst central area in the layout design of the wirings. It should benoted that a chip CHP and a plurality of leads LA arranged on themounting surface of the wiring substrate WCB are also shown in atransparent manner in FIG. 32. Further, the peripheral area PA, thefirst central area CA1, and the second central area CA2 are hatched inFIG. 32 in order to easily view the drawing. Furthermore, since theperipheral area PA is the same as that explained in the firstembodiment, the explanation thereof will be omitted.

The first central area CA1 is an area where lands LD2 having the NSMDstructure and to which lead-out wiring parts WB are connected arearranged, and is arranged inside the peripheral area PA while beingsurrounded by the peripheral area PA. The first central area CA1 isarranged between the peripheral area PA and the second central area CA2.The leads LA in the chip loading surface of the wiring substrate WCB arearranged at positions overlapping with the first central area CA1 intransparent plan view. That is, the leads LA arranged in the chiploading surface of the wiring substrate WCB overlap with the lands LD2arranged on the mounting surface of the wiring substrate WCB intransparent plan view. The structure of each land arranged in the firstcentral area CA1 corresponds to the structure exemplified on the leftside of each of FIGS. 16 to 18.

It should be noted that an empty area FA1 is arranged between the firstcentral area CA1 and the peripheral area PA. However, the empty area FA1and the distance Fd1 thereof are the same as the empty area FA and thedistance Fd thereof in the first embodiment, and thus the explanationthereof will be omitted. Further, the distance Dsd (see FIG. 14) betweenthe lands (the first reference land and the second reference land) LD1and LD2 arranged at positions closest to each other among the lands LD1and LD2 is also the same as that in the first embodiment, and thus theexplanation thereof will be omitted. Furthermore, the definition of theouter peripheral position of the first central area CA1 is the same asthat of the outer peripheral position of the central area CA of thefirst embodiment, and thus the explanation thereof will be omitted.

The second central area CA2 is arranged inside the first central areaCA1 while being surrounded by the first central area CA1. The secondcentral area CA2 is slightly larger than the plane area of the chip CHP,and is arranged while including the chip CHP in transparent plan view.The leads LA in the chip loading surface of the wiring substrate WCB donot overlap with the second central area CA2 in transparent plan view.That is, the leads LA arranged in the chip loading surface of the wiringsubstrate WCB do not overlap with a plurality of lands (third lands) LD4arranged in the second central area CA2 of the mounting surface of thewiring substrate WCB in transparent plan view. Therefore, the lands LD4arranged in the second central area CA2 may have the NSMD structure andthe land-on-through-hole structure, the NSMD structure and the landstructure in which the lead-out wiring parts WB are connected, or bothstructures. In this case, as shown in FIG. 34, the lands LD4 arranged inthe second central area CA2 have, for example, the NSMD structure andthe land-on-through-hole structure.

That is, an opening portion (third opening portion) KB3 (KB) having alarger diameter than the land LD4 and including the land LD4 is formedin a solder resist SR2. Since the lead-out wiring part WB is notconnected with the land LD4, the upper surface and the entire sidesurface of the land LD4 are exposed from the opening portion KB3.Further, the land LD4 is electrically connected with a through-hole landTLA formed on the chip loading surface of a substrate SB through athrough-hole wiring (third through-hole wiring) WT3 (WT) formed in athrough-hole (third through-hole) TH3 (TH). It should be noted that theconcrete structure of the land LD4 is the same as the structureexemplified on the right side of each of FIGS. 16 to 18. Further, thediameter of the opening portion KB3 is the same as that of the openingportion KB (KB1 and KB2). Furthermore, the diameter of the through-holeTH3 is the same as that of the through-hole TH (TH1 and TH2).

In addition to the effects obtained in the first embodiment, thefollowing effects can be obtained in the second embodiment. That is,since the wiring lengths of signal wirings can be shortened by using thelands LD4 having the land-on-through-hole structure and the through-holewirings WT3 arranged directly under the chip CHP as the signal wirings,the operation speed of the semiconductor device 1 can be improved.Further, the lands LD4 having the land-on-through-hole structure and thethrough-hole wirings WT3 arranged directly under the chip CHP may beused as power supply wirings (power supply wirings on the high potentialside and power supply (for example, 0V at GND) wirings on the referencepotential side). Accordingly, since the wiring lengths of the powersupply wirings can be shortened, stable power supply potential can besupplied to the integrated circuit of the chip CHP. Therefore, theoperation reliability of the semiconductor device 1 can be improved.Further, since the dissipation of heat generated in the chip CHP duringthe operation of the semiconductor device 1 can be improved by allowingthe through-hole wirings WT3 arranged directly under the chip CHP tohave a metal-filled structure shown in FIG. 18, the operationreliability of the semiconductor device 1 can be improved.

Further, an empty area FA2 is arranged even between the second centralarea CA2 and the first central area CA1. The distance (fourth distance)Fd2 of the empty area FA2 is the same as the distance Fd of the emptyarea FA in the first embodiment, and thus the explanation thereof willbe omitted. The distance (second distance) between the lands (the thirdreference land and the fourth reference land) LD2 and LD4 arranged atpositions closest to each other among the lands LD2 of the first centralarea CA1 and the lands LD4 of the second central area CA2 is the same asthe distance Dsd (see FIG. 14) between the lands LD1 and LD2 describedin the first embodiment, and thus the explanation thereof will beomitted.

Here, the inner peripheral position (range setting) of the first centralarea CA will be described with reference to FIG. 35. It should be notedthat a solder resist SR1 is hatched in FIG. 35 in order to easily viewthe drawing.

As similar to the above, it is conceivable that the land having theland-on-through-hole structure may be arranged on the inner side (thecentral side of the wiring substrate WCB: the left side of FIG. 35) thanthe leads LA2 (LA). Actually, however, the wiring parts WA on the innerside than the leads LA2 are also densely arranged. Thus, if the landhaving the land-on-through-hole structure is arranged while overlappingwith the dense area of the wiring parts WA in transparent plan view, itis difficult to route the wirings of the wiring substrate WCB as similarto the arrangement area of the leads LA.

Accordingly, in the second embodiment, the inner peripheral side of thefirst central area CA1 is extended to a part of the arrangement area ofthe wiring parts WA on the inner side than the leads LA2. That is, theinner peripheral position of the first central area CA1 is set at theposition X6 obtained by subtracting the length Rc5 from the length Rc4from the center position X0 of the chip CHP to the innermost end of thelead LA2. The length Rc5 is equal to or larger than, for example, thediameter of each land LD (LD1 to LD4). The condition of the length Rc5can be set to the same length condition as described for the distance Fdof the first embodiment. By configuring as described above, the densearea of the wiring parts WA on the inner side than the leads LA2 can bealso used as the arrangement area of the lands LD2 having the NSMDstructure and to which the lead-out wiring parts WB are connected. Thus,the wirings of the wiring substrate WCB can be easily routed.

On the other hand, the lands LD4 having the land-on-through-holestructure are arranged in the second central area CA2. Thus, for thesame reason as described above, if the second central area CA2 entersthe dense area of the wiring parts WA on the chip loading surface of thewiring substrate WCB, it is difficult to route the wirings of the wiringsubstrate WCB.

Therefore, in the second embodiment, the outer periphery of the secondcentral area CA2 is defined so as to be arranged at the position X7 thatis apart from the position X6 of the inner periphery of the firstcentral area CA1 only by the distance Fd2. That is, the second centralarea CA2 is set at the position X7 obtained by subtracting only thedistance Fd2 from the length Rc6 from the center position X0 of the chipCHP to the position X6 of the inner periphery of the first central areaCA1. By configuring as described above, the land LD4 having theland-on-through-hole structure is not arranged in the dense area of thewiring parts WA on the inner side than the leads LA2. Thus, the wiringsof the wiring substrate WCB can be easily routed. It should be notedthat the center of the chip CHP is used as a reference when setting theboundary (the outer periphery and the inner periphery) positions of thefirst central area CA1 and the second central area CA2 in the aboveexample. However, the present invention is not limited thereto. Forexample, the position of the center of the wiring substrate WCB, theposition of the outer periphery of the wiring substrate WCB, or thealready-determined boundary position of the peripheral area PA, thefirst central area CA1, or the second central area CA2 may be used as areference.

The invention made by the inventors has been concretely described aboveon the basis of the embodiments. However, it is obvious that the presentinvention is not limited to the above-described embodiments, and can bevariously changed without departing from the gist thereof.

What is claimed is:
 1. A semiconductor device comprising: a wiringsubstrate including a base material having a first surface and a secondsurface opposite to the first surface, a plurality of leads arranged onthe first surface of the base material, a first insulating film providedon the first surface of the base material such that the plurality ofleads is exposed, a plurality of lands arranged on the second surface ofthe base material, a second insulating film provided on the secondsurface of the base material such that the plurality of lands isexposed, a plurality of through-holes each penetrating between the firstsurface and the second surface of the base material, and a plurality ofthrough-hole wirings formed inside the plurality of through holes,respectively, and electrically connecting the plurality of leads withthe plurality of lands, respectively; a semiconductor chip having athird surface, a plurality of electrodes formed on the third surface,and a fourth surface opposite to the third surface, and mounted over thefirst surface of the wiring substrate such that the fourth surface facesthe first surface of the base material; a plurality of wireselectrically connecting the plurality of electrodes of the semiconductorchip with the plurality of leads of the wiring substrate, respectively;a resin sealing body sealing the semiconductor chip and the plurality ofwires; and an external terminal provided on each of the plurality oflands, wherein the plurality of lands has: a plurality of first landsthat does not overlap with the plurality of leads in transparent planview and that is arranged along an edge of the base material, and aplurality of second lands that is located on the inner side than theplurality of first lands in plan view, that overlaps with the pluralityof leads in transparent plan view, and that is arranged along the edgeof the base material, wherein a wiring part formed on the second surfaceof the base material is connected to each of the plurality of secondlands, wherein the plurality of second lands has a second reference landlocated closest to a first reference land among the plurality of firstlands, wherein a first distance between the first reference land and thesecond reference land is larger than a distance between two lands, thatare adjacent to each other along the edge of the base material, amongthe plurality of first lands, wherein the plurality of through-holewirings has: a first through-hole wiring electrically connected with thefirst land, and a second through-hole wiring electrically connected withthe second land via the wiring part, wherein a first through-hole,inside which the first through-hole wiring is formed, among theplurality of through holes overlaps with the first land in plan view,wherein a second through-hole, inside which the second through-holewiring is formed, among the plurality of through-holes does not overlapwith the second land in plan view, wherein a plurality of openingportions that respectively exposes the plurality of lands such that theplurality of lands is respectively located within the plurality ofopening portions in plan view is formed in the second insulating film,and wherein the plurality of opening portions has: a first openingportion exposing the first land, and a second opening portion exposingthe second land and a part of the wiring part.
 2. The semiconductordevice according to claim 1, wherein the diameter of each of theplurality of lands is larger than an adjacent distance between theplurality of leads.
 3. The semiconductor device according to claim 1,wherein the plurality of first lands and the plurality of second landsare arranged in plural rows.
 4. The semiconductor device according toclaim 1, wherein the resin sealing body covers the entire area of thefirst surface of the base material.
 5. The semiconductor deviceaccording to claim 1, wherein the first distance is larger than thediameter of each of the plurality of lands.
 6. The semiconductor deviceaccording to claim 1, wherein the first distance is larger than anadjacent pitch between two lands, that are adjacent to each other alongthe edge of the base material, among the plurality of first lands. 7.The semiconductor device according to claim 1, wherein the plurality oflands has a plurality of third lands arranged along the edge of the basematerial at a position that is an area surrounded by the arrangementarea of the plurality of second lands and that does not overlap with theplurality of leads in transparent plan view, wherein the plurality ofthird lands has a fourth reference land located closest to a thirdreference land among the plurality of second lands, and wherein a seconddistance between the third reference land and the fourth reference landis larger than a distance between two lands, that are adjacent to eachother along the edge of the base material, among the plurality of firstlands.
 8. The semiconductor device according to claim 7, wherein theplurality of third lands overlap with the semiconductor chip intransparent plan view.
 9. The semiconductor device according to claim 7,wherein the plurality of through-hole wirings has a third through-holewiring electrically connected with the third land, wherein a thirdthrough-hole, inside which the third through-hole wiring is formed,among the plurality of through-holes overlaps with the third land inplan view, and wherein the plurality of opening portions of the secondinsulating film has a third opening portion that exposes the third landsuch that the third land is located within the third opening portion inplan view.
 10. A semiconductor device comprising: a wiring substrateincluding a base material having a first surface and a second surfaceopposite to the first surface, a plurality of leads arranged on thefirst surface of the base material, a first insulating film provided onthe first surface of the base material such that the plurality of leadsis exposed, a plurality of lands arranged on the second surface of thebase material, a second insulating film provided on the second surfaceof the base material such that the plurality of lands is exposed, aplurality of through-holes each penetrating between the first surfaceand the second surface of the base material, and a plurality ofthrough-hole wirings formed inside the plurality of through-holes,respectively, and electrically connecting the plurality of leads withthe plurality of lands, respectively; a semiconductor chip having athird surface, a plurality of electrodes formed on the third surface,and a fourth surface opposite to the third surface, and mounted over thefirst surface of the wiring substrate; a plurality of wires electricallyconnecting the plurality of electrodes of the semiconductor chip withthe plurality of leads of the wiring substrate, respectively; a resinsealing body sealing the semiconductor chip and the plurality of wires;and an external terminal provided on each of the plurality of lands,wherein the plurality of leads does not overlap with a first area on theouter peripheral side on the second surface of the base material intransparent plan view, but overlaps with a second area on the inner sidethan the first area in transparent plan view, wherein the plurality oflands has: a plurality of first lands arranged along an edge of the basematerial in the first area, and a plurality of second lands arrangedalong the edge of the base material in the second area, wherein a wiringpart formed on the second surface of the base material is connected toeach of the plurality of second lands, wherein a third distance betweenthe first area and the second area is larger than a distance between twolands that are adjacent to each other along the edge of the substrateamong the first lands, wherein the plurality of through-hole wiringshas: a first through-hole wiring electrically connected with the firstland, and a second through-hole wiring electrically connected with thesecond land via the wiring part, wherein a first through-hole, insidewhich the first through-hole wiring is formed, among the plurality ofthrough-holes overlaps with the first land in plan view, wherein asecond through-hole, inside which the second through-hole wiring isformed, among the plurality of through-holes does not overlap with thesecond land in plan view, wherein a plurality of opening portions thatrespectively exposes the plurality of lands such that the plurality oflands is respectively located within the plurality of opening portionsin plan view is formed in the second insulating film, and wherein theplurality of opening portions has: a first opening portion exposing thefirst land, and a second opening portion exposing the second land and apart of the wiring part.
 11. The semiconductor device according to claim10, wherein the diameter of the land is larger than an adjacent distancebetween the leads.
 12. The semiconductor device according to claim 10,wherein the first lands and the second lands are arranged while forminga plurality of rows.
 13. The semiconductor device according to claim 10,wherein the resin sealing body covers the entire area of the firstsurface of the substrate.
 14. The semiconductor device according toclaim 10, wherein the third distance is larger than the diameter of theland.
 15. The semiconductor device according to claim 10, wherein thethird distance is larger than a distance between two lands that areadjacent to each other along the edge of the substrate among the firstlands.
 16. The semiconductor device according to claim 10, wherein thelands have a plurality of third lands arranged along the edge of thesubstrate in a third area that is located on the inner side than thesecond area and does not overlap with the leads in transparent planview, and wherein a fourth distance between the second area and thethird area is larger than a distance between two lands that are adjacentto each other along the edge of the substrate among the first lands. 17.The semiconductor device according to claim 16, wherein the third landsoverlap with the semiconductor chip in transparent plan view.
 18. Thesemiconductor device according to claim 16, wherein the through-holewirings have a third through-hole wiring electrically connected with thethird land, wherein a third through-hole, inside which the third throughhole wiring is formed among the through-holes overlaps with the thirdland in plan view, and wherein the opening portions of the secondinsulating film have a third opening portion exposing the third landwhile being included in plan view.